Systems for displaying images that appear three-dimensional (“3D”) have been available for many years. Typically, in order to create a 3D image, two separate single color, two-dimensional images are projected onto a screen, which is viewed by a viewer wearing goggles or glasses having right and left color filters. The right filter passes the first color (e.g. red) of the image to the right eye while the left filter blocks the red light from reaching the left eye. Meanwhile, the left filter passes the other color (e.g., blue) to the left eye while the right filter blocks the blue light from reaching the right eye. As a result, the viewer's eyes see different images, which the brain interprets as a single image having depth (i.e., the third dimension).
An alternative technique for displaying a 3D image projects two separate images, each having a different polarization mode, on the screen. In this case, the viewer's glasses have polarization filters that enable slightly different images to reach the viewer's eyes. As with color-based projection systems, the viewer's brain interprets the different images as a single image having depth. Polarization-based 3D projection systems typically provide better color reproduction than color-based 3D projection systems; however, the polarization filters block as much as 50% of the light reaching each eye. As a result, the images are typically projected at high intensity to offset the loss.
Unfortunately, conventional 3D projection systems are typically large, expensive, and include optical systems that require complex alignment to attain and maintain quality images. As a result, an improved 3D projection system that is cheaper to make, smaller, optically efficient, and less complex is desirable.